Long-term surveillance provides real-world evidences of safety and effectiveness in intravitreal aflibercept treatment for age-related macular degeneration.

This prospective, multicentre, postmarketing surveillance were conducted to report on the long-term safety and effectiveness of intravitreal aflibercept (IVT-AFL) treatment in clinical practice of Japanese patients with neovascular age-related macular degeneration (nAMD) who newly initiated IVT-AFL treatment. The primary outcomes were the incidence of adverse events (AEs) and of adverse drug reactions (ADRs) over 36 months. Number of injections, timing of ADR occurrence, and some effectiveness index were also summarised. A total of 3,872 patients received 7.2 ± 5.8 (mean ± standard deviation) injections, and AEs occurred in 5.73% of patients. ADRs were reported in 2.76% of patients, with ocular and nonocular ADRs in 2.07% and 0.72% of patients, respectively. Most vitreo-retinal events developed within 6 months of initial IVT-AFL treatment, and most instances of increased intraocular pressure and cerebral infarction developed after 6 months of follow-up. Mean best-corrected visual acuity and central retinal thickness were numerically better throughout the follow-up period compared with baseline. These results indicated acceptable tolerability and effectiveness of IVT-AFL treatment in patients with nAMD in clinical practice in Japan. Information regarding the risk and the timing of ADRs is valuable for safe and effective long-term treatment of patients with nAMD.Trial registration number: NCT01756248.

Astaxanthin increases choroidal blood flow velocity.

PURPOSE: Previous studies have reported that astaxanthin (AXT) has antioxidative and anti-inflammatory effects in addition to its ability to shorten blood transit times. As laser speckle flowgraphy (LSFG) can noninvasively visualize the hemodynamics of the choroidal circulation, we used the technique to evaluate whether continuous ingestion of 12 mg of AXT per day could increase quantitative blood flow velocity. METHODS: In this randomized, double-blind, placebo-controlled study, we examined 20 healthy volunteers who ingested 12 mg AXT or placebo capsules over a 4-week period. LSFG was measured in the right eyes of all subjects at pre-ingestion, and at 2 and 4 weeks after the treatment of AXT. LSFG values were used to calculate the square blur rate (SBR), which is a quantitative index of relative blood flow velocity. RESULTS: A significant increase of the macular SBR was seen 4 weeks after AXT ingestion when compared to the pre-ingestion values (Wilcoxon signed-rank test, P = 0.018). In contrast, no statistical difference in the macular SBR was detected in the placebo group (Friedman test, P = 0.598). No subjective or objective adverse events were found after the 12-mg AXT ingestion. CONCLUSIONS: Results suggest that administration of AXT over a 4-week period can elevate the choroidal blood flow velocity without any adverse effects.

[Pathogenesis of infectious conjunctivitis in Nepal].

PURPOSE: We investigated human adenovirus (HAdV) and Chlamydia trachomatis in patients with infectious conjunctivitis in Nepal. METHOD: We obtained swabs from 6 patients with infectious conjunctivitis in a remote area near the Indian border (group A), and from 30 patients at the B. P. Koirala Eye Center of Tribhuvan University Teaching Hospital in Kathmandu (group B). Rapid diagnosis of HAdV was conducted in Nepal, using Capilia adeno eye (Capilia), a rapid adenoviral antigen diagnostic kit using immunochromatography. Residual swabs were brought to Japan and examined for HAdV and Chlamydia trachomatis using polymerase chain reaction (PCR). Etiological analysis of 214 patients with trachoma was also investigated by PCR. RESULTS: Capilia results were negative for the six samples of group A and positive for 13 patients (43%) in group B. PCR showed one (17%) as positive in group A and 30 (100%)in group B. The serotype of all HAdV positive samples was HAdV-8. C serovar of Chlamydia trachomatis was detected in ninety seven cases out of 214 patients with trachoma. CONCLUSION: HAdV-8 and Chlamydia trachomatis serotype C seem to be prevalent in Nepal.

Inhibition of choroidal neovascularization with an anti-inflammatory carotenoid astaxanthin.

PURPOSE: Astaxanthin (AST) is a carotenoid found in marine animals and vegetables. The purpose of the present study was to investigate the effect of AST on the development of experimental choroidal neovascularization (CNV) with underlying cellular and molecular mechanisms. METHODS: Laser photocoagulation was used to induce CNV in C57BL/6J mice. Mice were pretreated with intraperitoneal injections of AST daily for 3 days before photocoagulation, and treatments were continued daily until the end of the study. CNV response was analyzed by volumetric measurements 1 week after laser injury. Retinal pigment epithelium-choroid levels of IkappaB-alpha, intercellular adhesion molecule (ICAM)-1, monocyte chemotactic protein (MCP)-1, interleukin (IL)-6, vascular endothelial growth factor (VEGF), VEGF receptor (VEGFR)-1, and VEGFR-2 were examined by Western blotting or ELISA. AST was applied to capillary endothelial (b-End3) cells, macrophages, and RPE cells to analyze the activation of NF-kappaB and the expression of inflammatory molecules. RESULTS: The index of CNV volume was significantly suppressed by treatment with AST compared with that in vehicle-treated animals. AST treatment led to significant inhibition of macrophage infiltration into CNV and of the in vivo and in vitro expression of inflammation-related molecules, including VEGF, IL-6, ICAM-1, MCP-1, VEGFR-1, and VEGFR-2. Importantly, AST suppressed the activation of the NF-kappaB pathway, including IkappaB-alpha degradation and p65 nuclear translocation. CONCLUSIONS: AST treatment, together with inflammatory processes including NF-kappaB activation, subsequent upregulation of inflammatory molecules, and macrophage infiltration, led to significant suppression of CNV development. The present study suggests the possibility of AST supplementation as a therapeutic strategy to suppress CNV associated with AMD.

Macular pigment lutein is antiinflammatory in preventing choroidal neovascularization.

BACKGROUND: Choroidal neovascularization (CNV) is a critical pathogenesis in age-related macular degeneration, the most common cause of blindness in the developed countries. The aim of the current study was to investigate the effect of lutein supplementation on the development of the murine model of laser-induced CNV together with underlying molecular mechanisms. METHODS AND RESULTS: Mice were orally pretreated with lutein daily from 3 days before laser photocoagulation until the end of the study. The index of CNV volume was significantly suppressed by the treatment with lutein, compared with vehicle-treated animals. Lutein treatment led to significant inhibition of macrophage infiltration into CNV and of the in vivo and in vitro expression of inflammation-related molecules including vascular endothelial growth factor, monocyte chemotactic protein -1, and intercellular adhesion molecule-1. Importantly, lutein suppressed IkappaB-alpha degradation and nuclear translocation of nuclear factor (NF)-kappaB p65 both in vivo and in vitro. Additionally, the development of CNV was significantly suppressed by inhibiting NF-kappaB p65 nuclear translocation, to the levels seen in the lutein treatment. CONCLUSIONS: Lutein treatment led to significant suppression of CNV development together with inflammatory processes including NF-kappaB activation and subsequent upregulation of inflammatory molecules, providing molecular evidence of potential validity of lutein supplementation as a therapeutic strategy to suppress CNV.

Expression of erythropoietin receptor in human epiretinal membrane of proliferative diabetic retinopathy.

PURPOSE: It is widely accepted that intravitreous levels of erythropoietin (Epo) are elevated in patients with ischaemic retinal diseases such as proliferative diabetic retinopathy (PDR). The aim of this study was to examine the expression of Epo and the Epo receptor (EpoR) in epiretinal membranes with and without diabetes. METHODS: Eighteen epiretinal membranes (PDR (n = 10), idiopathic epiretinal membranes (IERMs) without diabetes (n = 4) and inner limiting membranes (ILMs) (n = 4)) were obtained during pars plana vitrectomy. Formalin-fixed and paraffin-embedded tissues were examined by immunohistochemistry with anti-Epo and EpoR antibodies. RESULTS: The histopathological findings demonstrated that PDR membranes consisted of a variety of endothelial cells forming a microvascular cavity with red blood cells and non-vascular stromal mononuclear cells. Membranous and cytoplasmic immunoreactivity for EpoR was strongly detected in endothelial cells and stromal cells in all PDR patients. Although microvessels were not observed in IERMs and ILMs, immunoreactivity for EpoR was noted in the cellular component of IERMs, and was weakly detected in ILMs. Epo was not expressed in any membrane. CONCLUSION: EpoR was strongly expressed in microvessels of all PDR membranes. The in vivo evidence in this study suggests that Epo in the vitreous binds to EpoR in PDR membranes, which subsequently leads to the proliferation of new retinal vessels. EpoR immunoreactivity in non-vascular stromal cells in PDR membranes, and IERMs and ILMs might be indirectly correlated with ischaemia.

Inhibition of nuclear factor-kappa B activation attenuates hydrogen peroxide-induced cytotoxicity in human lens epithelial cells.

AIMS: Hydrogen peroxide (H(2)O(2)) is the major oxidant involved in cataract formation. Lens epithelial cells have been suggested to be the first site of oxidative damage. The authors investigated the relationship between H(2)O(2)-induced cytotoxicity and activation of nuclear factor kappa B (NF-kappaB) in human lens epithelial (HLE) cells. METHODS: HLE B-3 cells were stimulated by various concentrations of H(2)O(2) in the presence or absence of pyrrolidine dithiocarbamate (PDTC), a potent inhibitor of NF-kappaB. H(2)O(2)-induced cytotoxicity was measured by lactate dehydrogenase cytotoxicity assay. Translocation of NF-kappaB was examined by Western blot and immunocytochemistry using anti-p65 antibody. RESULTS: H(2)O(2)-induced cytotoxicity increased in a concentration-dependent manner. PDTC treatment significantly suppressed the cytotoxicity induced by H(2)O(2). After stimulated with H(2)O(2), NF-kappaB was found translocated from cytoplasm into the nuclei. PDTC treatment also inhibited the translocation of NF-kappaB. CONCLUSIONS: NF-kappaB signal pathway may be important in the development of H(2)O(2)-induced damage in HLE cells that is involved in cataractogenesis.

Positive association of pigment epithelium-derived factor with total antioxidant capacity in the vitreous fluid of patients with proliferative diabetic retinopathy.

BACKGROUND: Pigment epithelium-derived factor (PEDF), a glycoprotein with potent neuronal differentiating activity, was recently found to inhibit advanced glycation end product (AGE)-induced retinal hyperpermeability and angiogenesis through its antioxidative properties, suggesting that it may exert beneficial effects on diabetic retinopathy by acting as an endogenous antioxidant. However, the inter-relationship between PEDF and total antioxidant capacity in the eye remains to be elucidated. AIMS: To determine vitreous PEDF and total antioxidant levels in patients with proliferative diabetic retinopathy (PDR), and to investigate the relationship between them. METHODS: Vitreous levels of PEDF and total antioxidant capacity were measured by an ELISA in 39 eyes of 36 patients with diabetes and PDR and in 29 eyes of 29 controls without diabetes. RESULTS: Vitreous levels of total antioxidant capacity were significantly lower in patients with diabetes and PDR than in controls (mean (SD) 0.16 (0.05) vs 0.24 (0.09) mmol/l, respectively, p<0.001). PEDF levels correlated positively with total antioxidant status in the vitreous of patients with PDR (r = 0.37, p<0.05) and in controls (r = 0.41, p<0.05). Further, vitreous levels of PEDF in patients with PDR without vitreous haemorrhage (VH(-)) were significantly (p<0.05) decreased, compared with those in the controls or in patients with PDR with vitreous haemorrhage (VH(+); PDR VH(-), 4.5 (1.1) microg/ml; control, 7.4 (4.1) microg/ml; PDR VH(+) 8.5 (3.6) microg/ml). CONCLUSION: This study demonstrates that PEDF levels are associated with total antioxidant capacity of vitreous fluid in humans, and suggests that PEDF may act as an endogenous antioxidant in the eye and could play a protective role against PDR.

Increased expression of erythropoietin receptor in human pterygial tissues.

Erythropoietin (Epo) induces physiological activities such as cell proliferation, migration, and angiogenesis in Epo receptor (EpoR)-expressing vascular endothelial and tumor cells. Recently, it has been demonstrated that growth factor-independent proliferation is frequently observed during the cell transformation process. Pterygium is a fibrovascular proliferating tissue that includes transformed cells. The aim of this study was to examine the localization of Epo and EpoR proteins in human pterygial tissues. Eleven samples including nine pterygia and two normal bulbar conjunctivas, which were surgically excised, were studied. Formalin-fixed, paraffin-embedded tissue sections were constructed and then were examined by immunohistochemistry with anti-Epo and EpoR antibodies. Cytoplasmic immunoreactivity for EpoR was heterogeneously detected in basal and suprabasal cells of the pterygium epithelium. In the pterygium stroma, a variety of endothelial cells forming vascular cavities showed cytolasmic immunoreactivity for EpoR. In normal conjunctival epithelium, a few basal cells showed a weak homogeneous immunoreactivity for EpoR in the cytoplasm. The number of EpoR-expressing epithelial cells was much higher in the pterygium compared to the normal conjunctiva. EpoR expression was marginally detected in stromal microvessels of the normal conjunctiva. Immunoreactivity for Epo was not noted in pterygium epithelium and stroma, and in normal conjunctiva. These results suggest that the Epo-independent EpoR-signaling pathway plays a potential role in cell proliferation and angiogenesis in human pterygium.

Inhibitory effects of lutein on endotoxin-induced uveitis in Lewis rats.

PURPOSE: Lutein deposits in the macula and lens of human eyes with high concentration and is well known as an eye-protective nutrient for its beneficial effects on eye disease such as age-related macular degeneration and cataract. The purpose of the present study was to investigate the effects of lutein on endotoxin-induced uveitis (EIU) in rats. METHODS: EIU was induced in male Lewis rats by subcutaneous injection of 200 microg lipopolysaccharide. Lutein or dexamethasone was administered intravenously at 30 minutes before, at the same time as, and at 30 minutes after LPS treatment. The aqueous humor was collected at 24 hours after LPS injection, the number of infiltrating cells, the protein concentration, and the levels of nitric oxide (NO), tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, prostaglandin (PG)-E2, monocyte chemoattractant protein-1 (MCP-1), and macrophage inflammatory protein (MIP)-2 in the aqueous humor were determined. Immunohistochemical staining with a monoclonal antibody against activated nuclear factor (NF)-kappaB was performed to evaluate the effect of lutein on NF-kappaB activation in the iris-ciliary body (ICB) of rats. A mouse macrophage cell line (RAW264.7 cells) was stimulated with LPS in the presence or absence of lutein. Expression of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), and degradation of inhibitor kappaB (IkappaB) were analyzed by Western blot analysis. RESULTS: Lutein suppressed the development of EIU in a dose-dependent fashion. The anti-inflammatory effect of 100 mg/kg lutein was as strong as that of 1 mg/kg dexamethasone. Treatment with lutein reduced the concentrations of NO, TNF-alpha, IL-6, PGE2, MCP-1, and MIP-2 in aqueous humor. Lutein also suppressed the activation of NF-kappaB in the ICB as well as iNOS and COX-2 expression and IkappaB degradation in RAW cells. CONCLUSIONS: These findings indicate that lutein has anti-inflammatory effects on EIU by inhibiting the NF-kappaB dependent signaling pathway and the subsequent production of proinflammatory mediators.

Expression of cdc2 and p27(KIP1) phosphorylation in mitotic cells of the human retinoblastoma.

It was recently demonstrated that a lack of p27(KIP1) degradation resulted in the suppression of cdc2 activity and consequent inhibition of entry into the M-phase. The aim of this study was to examine the distribution of phosphorylated p27(KIP1) on threonine 187 (T187-phospho-p27) and cdc2 in mitotic cells of human retinoblastoma, a malignant retinal neoplasm. Several T187-phospho-p27-immunopositive cells were observed in mitotic retinoblastoma cells, but not in the normal retina. Immunoreactivity for T187-phospho-p27 was located in the prophase and metaphase of mitotic tumor cells. In contrast, tumor cells in the anaphase showed no immunoreactivity for T187-phospho-p27. Nuclear expression of cdc2 was detected in many retinoblastoma cells, including mitotic cells. The immunoreactivity in mitotic cells was located in the prophase, as well as metaphase. In contrast, anaphase cells did not show immunoreactivity. Double staining demonstrated the same localization of T187-phospho-p27 and cdc2 in mitotic cells. These results suggest that p27(KIP1) interacts with cdc2 in the M-phase of human retinoblastoma cells.

Phosphorylation of p27(KIP1) in lens epithelial cells after extraction of fiber cells.

Opacification of the posterior capsule depends on replication of the residual lens epithelial cells lining the capsule. However, the mechanisms in the regulation of lens cell proliferation have not been determined. The purpose of this study is to examine the expression of p27(KIP1), a cyclin-dependent kinase inhibitor, and its phosphorylation, and cyclin D1 in lens epithelial cells after extraction of fiber cells. C57Bl6 mice (12 weeks old) were anesthetized, and the lens fiber cells were surgically extracted. Eyeballs were collected and fixed at 15 min and 24 h after extraction with and without injection of a specific phosphorylated extracellular signal-regulated kinase (pERK) 1/2 inhibitor (PD98059) to the anterior chamber. Collected tissues were analyzed using immunohistochemistry with anti-p27(KIP1), anti-phosphorylated p27(KIP1) on serine 10 (s10-phospho-p27) and cyclin D1 antibodies. Human lens epithelial cells were cultured, and then were treated with and without 40 ng/ml human recombinant basic fibroblast growth factor (bFGF), which was analyzed by Western blot analysis. In the untreated lens, p27(KIP1) was not phosphorylated in the lens epithelial cells, although p27(KIP1)-positive nuclei were detected in the lens cells of the equatorial region. Immunoreactivity for cyclin D1 was hardly detected in the lens. Nuclear immunoreactivity for p27(KIP1) and s10-phospho-p27 was observed in several lens cells of the equatorial region 15 min after extraction of fiber cells. Western blotting demonstrated that the p27(KIP1) phosphorylation form was upregulated 15 min after bFGF treatment in cultured lens epithelial cells. Many cyclin D1-positive nuclei were noted 24 h after the surgery. p27(KIP1) phosphorylation and cyclin D1 induction were inhibited by PD98059. s10-phospho-p27 and p27(KIP1) immunoreactivity was undetected in the lens cells 24 h after the extraction of fiber cells. It is possible that the phosphorylation of p27(KIP1), and cyclin D1 expression are regulated by the ERK pathway in lens cells after the extraction of fiber cells.

Phosphorylation of p27(KIP1) in the mitotic cells of the corneal epithelium.

PURPOSE: The mechanism in regulation of the cell cycle and proliferation of corneal epithelium in the homeostatic ocular surface remains unclear. The aim of this study is to examine the expression of p27(KIP1) and its phosphorylation in corneal epithelium. METHODS: The eyes of C57BL/6 mice (7 weeks old) were enucleated. Formalin-fixed and paraffin-embedded tissue sections were examined using immunohistochemistry with anti-p27(KIP1), threonine 187 phosphorylated p27(KIP1) (T187-phospho-p27), and phosphorylated Histon H3 (pHiston H3) antibodies. Anti-T187-phospho-p27 and anti-pHiston H3 polyclonal antibodies were used for parallel immunofluorescent staining. RESULTS: pHiston H3-immunopositive cells were noted in basal cells of the corneal epithelium. At high magnification of DAPI nuclear staining, mitotic and non-mitotic cells were observed in corneal basal layer. p27(KIP1)-positive nuclei were detected in corneal basal cells, where non-mitotic basal cells were located. In contrast, mitotic cells showed under detectable level on p27(KIP1) immunoreactivity. Immunoreactivity for T187-phospho-p27 was detected in basal cells of the corneal epithelium. At high magnification, it was confirmed that the immunopositive cells were mitotic cells. Immunoreactivity of T187-phospho-p27 as well as pHiston H3 was localized in the same corneal basal cells using double-staining immunohistochemistry. CONCLUSIONS: These results suggested that degradation of p27(KIP1) regulates progression into mitosis in corneal basal cells.

Immunolocalization of cyclin D1 in the developing lens of c-maf -/- mice.

The maf gene encodes a transcription factor protein containing a typical basic/leucine zipper domain structure, a motif for protein dimerization and DNA binding. It has been demonstrated that maf family genes have important roles in embryonic development and cellular differentiation. In this study, localization of cyclin D1, one of the cell cycle-related molecules, was examined immunohistochemically in developing lens cells of c-maf knockout (-/-) mice. At embryonic day 14 in wild-type mice, lens cells consisted of round epithelial cells in a single layer and regularly arranged elongated lens cells, indicating primary lens fiber cells. Cyclin D1-positive nuclei were observed in the lens epithelial cells, whereas cyclin D1 was not detected in the primary lens fiber cells. In c-maf -/- mice, a variety of round epithelial cells were located in the anterior and posterior lens. Many cyclin D1-positive nuclei were observed in lens epithelial cells as well as posterior lens cells. These results are consistent with c-maf playing a role in the regulation of cyclin D1 in developing lens cells.

Anti-inflammatory effects of aronia extract on rat endotoxin-induced uveitis.

PURPOSE: Aronia crude extract (ACE) with high levels of polyphenol compounds has been reported to have antioxidative effects in vitro and in vivo. In this study, attention was focused on the antioxidant effect of ACE. The purpose of the present study was to investigate the effect of ACE on endotoxin-induced uveitis (EIU) in rats. In addition, the endotoxin-induced expression of the inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 proteins was investigated in a mouse macrophage cell line (RAW 264.7) treated with ACE in vitro, to clarify the anti-inflammatory effect. METHODS: EIU was induced in male Lewis rats by a footpad injection of lipopolysaccharide (LPS). Immediately after the LPS inoculation, 1, 10, or 100 mg ACE or 10 mg prednisolone was injected intravenously. After 24 hours, the aqueous humor was collected from both eyes, and the number of infiltrating cells, protein concentration, nitric oxide (NO), prostaglandin (PG)-E2, and TNF-alpha levels in the aqueous humor were determined. RAW 264.7 cells treated with various concentrations of ACE were incubated with 10 mug/mL LPS for 24 hours. Levels of NO, PGE2, and TNF-alpha were determined by an enzyme-linked immunosorbent assay. The expression of iNOS and COX-2 proteins was analyzed by Western blot analysis. RESULTS: The number of inflammatory cells, the protein concentrations, and the levels of NO, PGE2, and TNF-alpha in the aqueous humor in the groups treated with ACE were significantly decreased in a dose-dependent manner. In addition, the anti-inflammatory effect of 100 mg ACE was as strong as that of 10 mg prednisolone. The anti-inflammatory action of ACE was stronger than that of either quercetin or anthocyanin administered alone. ACE also suppressed LPS-induced iNOS and COX-2 protein expressions in RAW 264.7 cells in vitro in a dose-dependent manner. CONCLUSIONS: The results suggest that ACE has a dose-dependent anti-ocular inflammatory effect that is due to the direct blocking of the expression of the iNOS and COX-2 enzymes and leads to the suppression of the production of NO, PGE2, and TNF-alpha.

Phosphorylation of p27(KIP1) in the developing retina and retinoblastoma.

Cellular distribution of the p27(KIP1) protein and its phosphorylation on threonine (T) 187 in mouse retinas from three stages of development, and retinoblastoma were examined. Retinas in C57Bl6 mice at embryonic day (E) 14, postnatal day (P) 1 and P11 were analyzed using immunohistochemistry with anti-p27(KIP1), threonine-187-phosphorylated p27(KIP1) (T187-phospho-p27), bromodeoxyuridine (BrdU), proliferating cell nuclear antigen (PCNA) antibodies, and phosphorylated histon H3 (pHiston H3), which is a marker for cells in M phase. p27(KIP1) knockout (-/-) mice and human retinoblastoma were also analyzed. T187-phospho-p27 was detected in the outermost layer of the retina, whereas several neuroblastic cells expressed p27(KIP1) at E14. Many neuroblastic cells expressed BrdU in the middle layer. At P1, p27(KIP1) was detected in the ganglion cell layer and neuroblastic layer. T187-phospho-p27 was detected in the outermost layer, and that was localized in mitotic cells that also showed pHiston H3-positive. At P11, p27(KIP1) was detected in the inner nuclear layer, whereas T187-phospho-p27-positive or mitotic cells were not. BrdU positive nuclei were not detected in wild-type but were noted in the inner nuclear layer and the outer nuclear layer of the p27(KIP1) -/- mice retina at P11. In retinoblastoma, tumor cells formed numerous rosettes with Flexner-Wintersteiner rosettes. Several pHiston H3 -positive nuclei were noted in the tumor cells forming Flexner-Wintersteiner rosettes. Several T187-phospho-p27-positive nuclei were also detected in the mitotic cells forming Flexner-Wintersteiner rosettes. PCNA was expressed in rosette-forming cells. In conclusion, T187-phospho-p27(KIP1) was correlated with M phase of the cell cycle in the developing retina and retinoblastoma.

Expression of p27(KIP1) and cell proliferation in human retina and retinoblastoma.

BACKGROUND: Retinoblastoma is a rare cancer of the eye, in which biallelic inactivation of the retinoblastoma gene is a hallmark. Although retinoblastoma protein (Rb) and p27(KIP1) block the cell cycle transition from G1- to S-phase, the interaction has not been confirmed in vivo. The aim of this study was to examine the correlation between the expression of p27(KIP1) and cell proliferation in human retina and retinoblastoma. MATERIALS AND METHODS: Human retinoblastoma, surgically removed, was fixed by 4% paraformaldehyde. Then, paraffin-embedded tissue sections were examined using immunohistochemistry with anti-p27(KIP1) and anti-proliferating cell nuclear antigen (PCNA) antibodies. RESULTS: Retinoblastoma tissue was adjacent to the normal retina in which tumor cells with homogeneous nuclei proliferated and it was impossible to identify the layer structure of the inner nuclear layer (INL) and the outer nuclear layer (ONL). In normal retina, PCNA-positive nuclei were not observed, whereas nuclear immunoreactivity for PCNA was detected in a variety of tumor cells. Many p27(KIP1)-positive nuclei were detected in INL and ONL, while p27(KIP1) immunoreactivity was not detected in retinoblastoma cells. CONCLUSION: The correlation between disappearance of p27(KIP1) and induction of proliferation activity suggests that functional loss of Rb leads to down-regulation of p27(KIP1) and uncontrolled retinal cell proliferation.

Disappearance of p27(KIP1) and increase in proliferation of the lens cells after extraction of most of the fiber cells of the lens.

PURPOSE: Proliferation of the lens epithelial cells is involved in the fibrotic changes of lens capsules after cataract extraction. However, the mechanisms of the proliferation of the lens epithelial cells are largely unknown. The purpose of this study was to examine the correlation between the expression of p27(KIP1) and cell proliferation in the lens cells after the extraction of lens fiber cells. METHODS: At embryonic days (E) 14 and 18, the C57Bl6 mice were anesthetized and the embryos were surgically removed. The eyes were dissected from these embryos and also from mice 12 weeks after birth. The 12-week-old mice were anesthetized, and then the lens fiber cells were extracted. Normal eyes at E14 and 18 and eyes fixed at 15 min and 48 hr after the extraction of the lens fiber cells were analyzed using immunohistochemistry with anti-p27(KIP1), p57(KIP2), and phosphorylated extracellular signal-regulated kinase (phospho-ERK) 1/2 antibodies, and cells in the S phase of the cell cycle were also examined using anti-bromodeoxyuridine (BrdU) antibody. RESULTS: p27(KIP1) and p57(KIP2)-positive cells were present in the equatorial region of E14 mice. At E18, many lens fiber cells showed nuclear immunoreactivity for p27(KIP1), whereas a small number of cells were positive for p57(KIP2) in the equatorial region. At 12 weeks of age, all nuclei of the lens epithelial cells as well as lens fiber cells showed nuclear immunoreactivity for p27(KIP1). In contrast, p57(KIP2) and phospho-ERK1/2 were not expressed in the lens cells. At 15 min after the extraction of lens fiber cells, phospho-ERK1/2 as well as p27(KIP1) were detected in the lens cells. At 48 hr after the extraction of the lens fiber cells, a few p27(KIP1)-positive nuclei were observed in the equatorial region of the lens capsule. In contrast, many lens cells showed nuclear immunoreactivity for BrdU. CONCLUSIONS: These findings suggest that degradation of p27(KIP1) mediated by phosphorylation of ERK 1/2 is correlated with proliferation of the epithelial cells after the extraction of the lens fiber cells.

The effects of naringin and naringenin on endotoxin-induced uveitis in rats.

The aim of this study was to investigate the efficacy of naringin and naringenin on endotoxin- induced uveitis (EIU) in rats. EIU was induced in male Lewis rats by a footpad injection of lipopolysaccharide (LPS). The rats were injected intravenously with 0.4, 4, or 40 microg/kg naringin or naringenin. Each compound was administered three times, simultaneously, 30 min before and after the actual LPS injection. The aqueous humor was collected 24 h later from both eyes, and the number of cells infiltrating into the aqueous humor and the aqueous humor protein concentration were measured. The levels of prostaglandin E2 (PGE2) and nitric oxide (NO) were determined. Naringin and naringenin suppressed the development of EIU in a dose-dependent fashion. Both treatments with naringin and naringenin produced reductions in PGE2 and NO concentrations in the aqueous humor. In particular, 40 microM/kg of naringin and naringenin suppressed increases in cell count owing to LPS treatment by 31% and 38%, respectively. The possible mechanism for the antiocular inflammatory effect may be the suppression of PGE2 and NO by naringin and naringenin.

Inhibition of endotoxin-induced uveitis and potentiation of cyclooxygenase-2 protein expression by alpha-melanocyte-stimulating hormone.

PURPOSE: The efficacy of alpha-melanocyte-stimulating hormone (alpha-MSH) on endotoxin-induced uveitis (EIU) was investigated in rats. Several studies have demonstrated that there are various inflammatory reactions mediated by an alpha-MSH receptor in macrophages. In addition, as it is known that cyclooxygenase (COX)-2 is induced by a variety of stimuli and plays an important role in inflammation, COX-2 expression was also investigated in macrophage cells treated with alpha-MSH in vitro to clarify its anti-inflammatory effect. METHODS: EIU was induced in male Lewis rats by a footpad injection of lipopolysaccharide (LPS). The number of infiltrating cells and protein concentration in the aqueous humor collected 24 hours after the LPS treatment was determined. The levels of prostaglandin (PG)-E2, tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and monocyte chemoattractant protein (MCP)-1 production were determined. RAW 264.7 cells were pretreated with various concentrations of alpha-MSH for 24 hours and subsequently incubated with 10 microg/mL LPS for 24 hours. COX-2 protein expression was analyzed by Western blot analysis. RESULTS: alpha-MSH suppressed the development of EIU in a dose-dependent fashion. The treatment with alpha-MSH reduced the PGE2, TNF-alpha, IL-6, and MCP-1 concentrations in aqueous humor. The COX-2 protein expression in the alpha-MSH group decreased. CONCLUSIONS: This study suggests that alpha-MSH has an antiocular inflammatory effect, by suppression of PGE2, TNF-alpha, IL-6, and MCP-1 production and blocking of COX-2 expression.